共查询到20条相似文献,搜索用时 31 毫秒
1.
Vinutha V. Salian Badiadka Narayana Hemmige S. Yathirajan Mehmet Akkurt
mer elik Cem Cüneyt Ersanl Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(7):610-617
Four compounds are reported, all of which lie along a versatile reaction pathway which leads from simple carbonyl compounds to terphenyls. (2E)‐1‐(2,4‐Dichlorophenyl)‐3‐ [4‐(prop‐1‐en‐2‐yl)phenyl]prop‐2‐en‐1‐one, C18H14Cl2O, (I), prepared from 4‐(prop‐1‐en‐2‐yl)benzaldehyde and 2,4‐dichloroacetophenone, exhibits disorder over two sets of atomic sites having occupancies of 0.664 (6) and 0.336 (6). The related chalcone (2E)‐3‐(4‐chlorophenyl)‐1‐(4‐fluorophenyl)prop‐2‐en‐1‐one reacts with acetone to produce (5RS)‐3‐(4‐chlorophenyl)‐5‐[4‐(propan‐2‐yl)phenyl]cyclohex‐2‐en‐1‐one, C21H21ClO, (II), which exhibits enantiomeric disorder with occupancies at the reference site of 0.662 (4) and 0.338 (4) for the (5R) and (5S) forms; the same chalcone reacts with methyl 3‐oxobutanoate to give methyl (1RS,6SR)‐4‐(4‐chlorophenyl)‐6‐[4‐(propan‐2‐yl)phenyl]‐2‐oxocyclohex‐3‐ene‐1‐carboxylate, C23H23ClO3, (III), where the reference site contains both (1R,6S) and (1S,6R) forms with occupancies of 0.923 (3) and 0.077 (3), respectively. Oxidation, using 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone, of ethyl (1RS,6SR)‐6‐(4‐bromophenyl)‐4‐(4‐fluorophenyl)‐2‐oxocyclohex‐3‐ene‐1‐carboxylate, prepared in a similar manner to (II) and (III), produces ethyl 4′′‐bromo‐4‐fluoro‐5′‐hydroxy‐1,1′:3′,1′′‐terphenyl‐4′‐carboxylate, C21H16BrFO3, (IV), which crystallizes with Z′ = 2 in the space group P. There are no significant intermolecular interactions in the structures of compounds (I) and (II), but for the major disorder component of compound (III), the molecules are linked into sheets by a combination of C—H...O and C—H...π(arene) hydrogen bonds. The two independent molecules of compound (IV) form two different centrosymmetric dimers, one built from inversion‐related pairs of C—H...O hydrogen bonds and the other from inversion‐related pairs of C—H...π(arene) hydrogen bonds. Comparisons are made with related compounds. 相似文献
2.
Hiroshi Katagiri Masao Morimoto Kenichi Sakai 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o20-o24
The crystal structures of a pair of diastereomeric 1:2 salts of (R)‐ and (S)‐2‐methylpiperazine with (2S,3S)‐tartaric acid, namely (R)‐2‐methylpiperazinediium bis[hydrogen (2S,3S)‐tartrate] monohydrate, (I), and (S)‐2‐methylpiperazinediium bis[hydrogen (2S,3S)‐tartrate] monohydrate, (II), both C5H14N22+·2C4H5O6−·H2O, each reveal the formation of well‐defined head‐to‐tail‐connected hydrogen tartrate chains; these chains are linked into a two‐dimensional sheet via intermolecular hydrogen bonds involving hydroxy groups and water molecules, resulting in a layer structure. The (R)‐2‐methylpiperazinediium ions lie between the hydrogen tartrate layers in the most stable equatorial conformation in (I), whereas in (II), these ions are in an unstable axial position inside the more interconnected layers and form a larger number of intermolecular hydrogen bonds than are observed in (I). 相似文献
3.
Eugene Y. Cheung Matthew L. Peterson Renato Chiarella Bruce M. Foxman 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(5):o249-o251
The crystal structure of the antibiotic drug candidate RWJ‐416457 (systematic name: N‐{(5S)‐3‐[4‐(5,6‐dihydro‐2H,4H‐2‐methylpyrrolo[3,4‐c]pyrazol‐5‐yl)‐3‐fluorophenyl]‐2‐oxo‐1,3‐oxazolidin‐5‐yl}acetamide), C18H20FN5O3, which belongs to the first new class of antibiotics discovered in the past 30 years, has been determined at 150 K. Each molecule of this drug donates one hydrogen bond to a neighboring molecule and accepts one hydrogen bond to give (O=C—R—N—H...O=C—R—N—H...)n linkages along the b‐axis direction. The compound contains a pyrrolopyrazole ring, which, owing to its uncommon structure, has been shown to have particular effectiveness against multi‐drug‐resistant bacteria. 相似文献
4.
The 2,2′‐methylenebis[furan] ( 1 ) was converted to 1‐{(4R,6S))‐6‐[(2R)‐2,4‐dihydroxybutyl]‐2,2‐dimethyl‐1,3‐dioxan‐4‐yl}‐3‐[(2R,4R)‐tetrahydro‐4,6‐dihydroxy‐2H‐pyran‐2‐yl)propan‐2‐one ((+)‐ 18 ) and its (4S)‐epimer (?)‐ 19 with high stereo‐ and enantioselectivity (Schemes 1–3). Under acidic methanolysis, (+)‐ 18 yielded a single spiroketal, (3R)‐4‐{(1R,3S,4′R,5R,6′S,7R)‐3′,4′,5′,6′‐tetrahydro‐4′‐hydroxy‐7‐methoxyspiro[2,6‐dioxabicyclo[3.3.1]nonane‐3,2′‐[2H]pyran]‐6′‐yl}butane‐1,3‐diol ((?)‐ 20 ), in which both O‐atoms at the spiro center reside in equatorial positions, this being due to the tricyclic nature of (?)‐ 20 (methyl pyranoside formation). Compound (?)‐ 19 was converted similarly into the (4′S)‐epimeric tricyclic spiroketal (?)‐ 21 that also adopts a similar (3S)‐configuration and conformation. Spiroketals (?)‐ 20 , (?)‐ 21 and analog (?)‐ 23 , i.e., (1R,3S,4′R,5R,6′R)‐3′,4′,5′,6′‐tetrahydro‐6′‐[(2S)‐2‐hydroxybut‐3‐enyl]‐7‐methoxyspiro[2,6‐dioxabicyclo[3.3.1]nonane‐3,2′‐[2H]pyran]‐4′‐ol, derived from (?)‐ 20 , were assayed for their cytotoxicity toward murine P388 lymphocytic leukemia and six human cancer cell lines. Only racemic (±)‐ 21 showed evidence of cancer‐cell‐growth inhibition (P388, ED50: 6.9 μg/ml). 相似文献
5.
Saki Mohri Shinji Ohisa Katsuhiro Isozaki Noriyuki Yonezawa Akiko Okamoto 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(5):344-350
In the molecule of (2,7‐dimethoxynaphthalen‐1‐yl)(3‐fluorophenyl)methanone, C19H15FO3, (I), the dihedral angle between the plane of the naphthalene ring system and that of the benzene ring is 85.90 (5)°. The molecules exhibit axial chirality, with either an R‐ or an S‐stereogenic axis. In the crystal structure, each enantiomer is stacked into a columnar structure and the columns are arranged alternately to form a stripe structure. A pair of (methoxy)C—H...F hydrogen bonds and π–π interactions between the benzene rings of the aroyl groups link an R‐ and an S‐isomer to form a dimeric pair. These dimeric pairs are piled up in a columnar fashion through (benzene)C—H...O=C and (benzene)C—H...OCH3 hydrogen bonds. The analogous 1‐benzoylated compound, namely (2,7‐dimethoxynaphthalen‐1‐yl)(phenyl)methanone [Kato et al. (2010). Acta Cryst. E 66 , o2659], (II), affords three independent molecules having slightly different dihedral angles between the benzene and naphthalene rings. The three independent molecules form separate columns and the three types of column are connected to each other via two C—H...OCH3 hydrogen bonds and one C—H...O=C hydrogen bond. Two of the three columns are formed by the same enantiomeric isomer, whereas the remaining column consists of the counterpart isomer. In the case of the fluorinated 1‐benzoylated naphthalene analogue, namely (2,7‐dimethoxynaphthalen‐1‐yl)(4‐fluorophenyl)methanone [Watanabe et al. (2011). Acta Cryst. E 67 , o1466], (III), the molecular packing is similar to that of (I), i.e. it consists of stripes of R‐ and S‐enantiomeric columns. A pair of C—H...F hydrogen bonds between R‐ and S‐isomers, and C—H...O=C hydrogen bonds between R(or S)‐isomers, are also observed. Consequently, the stripe structure is apparently induced by the formation of R...S dimeric pairs stacked in a columnar fashion. The pair of C—H...F hydrogen bonds effectively stabilizes the dimeric pair of R‐ and S‐enantiomers. In addition, the co‐existence of C—H...F and C—H...O=C hydrogen bonds makes possible the formation of a structure with just one independent molecule. 相似文献
6.
Channappa N. Kavitha Hemmige S. Yathirajan Manpreet Kaur Eric C. Hosten Richard Betz Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):805-811
The structures of two salts of flunarizine, namely 1‐bis[(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4‐bis[(4‐fluorophenyl)methyl]‐1‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazin‐1‐ium pyridine‐3‐carboxylate}, C26H27F2N2+·C6H4NO2−, (I), the two ionic components are linked by a short charge‐assisted N—H...O hydrogen bond. The ion pairs are linked into a three‐dimensional framework structure by three independent C—H...O hydrogen bonds, augmented by C—H...π(arene) hydrogen bonds and an aromatic π–π stacking interaction. In flunarizinediium bis(4‐toluenesulfonate) dihydrate {systematic name: 1‐[bis(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine‐1,4‐diium bis(4‐methylbenzenesulfonate) dihydrate}, C26H28F2N22+·2C7H7O3S−·2H2O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N—H...O hydrogen bonds and four independent O—H...O hydrogen bonds, and these ribbons are linked to form a three‐dimensional framework by two independent C—H...O hydrogen bonds, but C—H...π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (II). Comparisons are made with some related structures. 相似文献
7.
Tullio Pilati Gianluigi Casalone 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o178-o180
The title diastereoisomers, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate and methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate–methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate (1/1), 2(S),5(S)‐C19H23N3O5·2(R),5(S)‐C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, 2(S),5(S)‐C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2‐(methoxycarbonyl)tetrahydropyrrole group. 相似文献
8.
Hiromitsu Sogawa Masashi Shiotsuki Fumio Sanda 《Journal of polymer science. Part A, Polymer chemistry》2012,50(10):2008-2018
Novel optically active substituted acetylenes HC? CCH2CR1(CO2CH3)NHR2 [(S)‐/(R)‐ 1 : R1 = H, R2 = Boc, (S)‐ 2 : R1 = CH3, R2 = Boc, (S)‐ 3 : R1 = H, R2 = Fmoc, (S)‐ 4 : R1 = CH3, R2 = Fmoc (Boc = tert‐butoxycarbonyl, Fmoc = 9‐fluorenylmethoxycarbonyl)] were synthesized from α‐propargylglycine and α‐propargylalanine, and polymerized with a rhodium catalyst to provide the polymers with number‐average molecular weights of 2400–38,900 in good yields. Polarimetric, circular dichroism (CD), and UV–vis spectroscopic analyses indicated that poly[(S)‐ 1 ], poly[(R)‐ 1 ], and poly[(S)‐ 4 ] formed predominantly one‐handed helical structures both in polar and nonpolar solvents. Poly[(S)‐ 1a ] carrying unprotected carboxy groups was obtained by alkaline hydrolysis of poly[(S)‐ 1 ], and poly[(S)‐ 4b ] carrying unprotected amino groups was obtained by removal of Fmoc groups of poly[(S)‐ 4 ] using piperidine. Poly[(S)‐ 1a ] and poly[(S)‐ 4b ] also exhibited clear CD signals, which were different from those of the precursors, poly[(S)‐ 1 ] and poly[(S)‐ 4 ]. The solution‐state IR measurement revealed the presence of intramolecular hydrogen bonding between the carbamate groups of poly[(S)‐ 1 ] and poly[(S)‐ 1a ]. The plus CD signal of poly[(S)‐ 1a ] turned into minus one on addition of alkali hydroxides and tetrabutylammonium fluoride, accompanying the red‐shift of λmax. The degree of λmax shift became large as the size of cation of the additive. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
9.
Hong‐Zhong Wang Xin Zhou Jia‐Xi Xu Sheng Jin Yue‐Ming Li AlbertS. C. Chan 《Journal of heterocyclic chemistry》2001,38(5):1031-1034
2‐Chloro‐4‐phenyl‐2a‐(4′‐methoxyphenyl)‐3,5‐dihydroazatetracyclic [1,2‐d]benzo [ 1,4]diazepin‐1 ‐one ( III a) and 2‐chloro‐4‐methyl‐2a‐(4′‐methoxyphenyl)‐3,5‐dihydroazatetracyclic[1,2‐d]‐benzo[1,4]diazepin‐1‐one ( III b) were synthesized. 1‐Benzoyl‐2‐phenyl‐4‐(4′‐methoxyphenyl)[1,4]‐benzodiazepine ( II a) was formed through benzoylation of starting material 2‐phenyl‐4‐(4′‐methoxyphenyl)‐[1,4]benzodiazepine ( I a) with the inversion of seven‐member ring boat conformation. The thus formed β‐lactams should have four pairs of stereoisomers. However, only one pair of enantiomers (2S,2R,4R) and (2R,2aS,4S) was obtained. The mechanism and stereochemistry of the formation of these compounds were studied on the basis of nmr spectroscopy and further confirmed by X‐ray diffraction. 相似文献
10.
Burkhardt I. Wilke Angela K. Goodenough Cory C. Bausch Erika N. Cline M. Leigh Abrams Effrat L. Fayer Dale C. Swenson Diana M. Cermak 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(12):o600-o605
The chiral compounds (6aS,9S,10aR)‐11,11‐dimethyl‐5,5‐dioxo‐2,3,8,9‐tetrahydro‐6H‐6a,9‐methanooxazaolo[2,3‐i][2,1]benzisothiazol‐10(7H)‐one, C12H17NO4S, (1), (7aS,10S,11aR)‐12,12‐dimethyl‐6,6‐dioxo‐3,4,9,10‐tetrahydro‐7H‐7a,10‐methano‐2H‐1,3‐oxazino[2,3‐i][2,1]benzisothiazol‐11(8H)‐one, C13H19NO4S, (2), (6aS,9S,10R,10aR)‐11,11‐dimethyl‐5,5‐dioxo‐2,3,7,8,9,10‐hexahydro‐6H‐6a,9‐methanooxazolo[2,3‐i][2,1]benzisothiazol‐10‐ol, C12H19NO4S, (3), and (7aS,10S,11R,11aR)‐12,12‐dimethyl‐6,6‐dioxo‐3,4,8,9,10,11‐hexahydro‐7H‐7a‐methano‐2H‐[1,3]oxazino[2,3‐i][2,1]benzisothiazol‐11‐ol, C13H21NO4S, (4), consist of a camphor core with a five‐membered spirosultaoxazolidine or six‐membered spirosultaoxazine, as both their keto and hydroxy derivatives. In each structure, the molecules are linked via hydrogen bonding to the sulfonyl O atoms, forming chains in the unit‐cell b‐axis direction. The chains interconnect via weak C—H...O interactions. The keto compounds have very similar packing but represent the highest melting [507–508 K for (1)] and lowest melting [457–458 K for (2)] solids. 相似文献
11.
Cocrystallization and configurations of myo‐inositol‐1,2‐l‐camphor acetals in two crystal structures
Graeme J. Gainsford Sylvia M. Baars Andrew Falshaw 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o169-o172
The inositol rings in (1S,2R,3R,4S,5S,6R,7S,8S,11S)‐myo‐inositol‐1,2‐camphor acetal {systematic name: (1R,2S,3S,4R,5S,6R)‐5,6‐[(1S,2S,4S)‐1,7,7‐trimethylbicyclo[2.2.1]heptane‐2,2‐diyldioxy]cyclohexane‐1,2,3,4‐tetrol}, C16H26O6, and (1R,2S,3S,4R,5R,6S,7R/S,8S,11S)‐myo‐inositol‐1,2‐camphor acetal trihydrate {systematic name: (1S,2R,3R,4S,5R,6S)‐5,6‐[(1S,4S,6R/S)‐1,7,7‐trimethylbicyclo[2.2.1]heptane‐2,2‐diyldioxy]cyclohexane‐1,2,3,4‐tetrol trihydrate}, C16H26O6·3H2O, adopt flattened chair conformations with the latter crystal containing two stereoisomers in a 0.684 (2):0.316 (2) ratio, similar to that found both in solution and by calculation. Both molecules pack in the crystals in similar two‐dimensional layers, utilizing strong O—H⋯O hydrogen bonds, with the trihydrate cell expanded to incorporate the additional hydrogen‐bonded water molecules. 相似文献
12.
Wojciech Nitek Agnieszka Kania Henryk Marona Anna M. Waszkielewicz Ewa esawska 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(7):681-689
Four crystal structures of 2‐amino‐N‐(dimethylphenoxyethyl)propan‐1‐ol derivatives, characterized by X‐ray diffraction analysis, are reported. The free base (R,S)‐2‐amino‐N‐[2‐(2,3‐dimethylphenoxy)ethyl]propan‐1‐ol, C13H21NO2, 1 , crystallizes in the space group P21/n, with two independent molecules in the asymmetric unit. The hydrochloride, (S)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium chloride, C13H22NO2+·Cl?, 2c , crystallizes in the space group P21, with one cation and one chloride anion in the asymmetric unit. The asymmetric unit of two salts of 2‐picolinic acid, namely, (R,S)‐N‐[2‐(2,3‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium pyridine‐2‐carboxylate, C13H22NO2+·C6H4NO2?, 1p , and (R)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium pyridine‐2‐carboxylate, C13H22NO2+·C6H4NO2?, 2p , consists of one cation and one 2‐picolinate anion. Salt 1p crystallizes in the triclinic centrosymmetric space group P, while salt 2p crystallizes in the space group P41212. The conformations of the amine fragments are contrasted and that of 2p is found to have an unusual antiperiplanar arrangement about the ether group. The crystal packing of 1 and 2c is dominated by hydrogen‐bonded chains, while the structures of the 2‐picolinate salts have hydrogen‐bonded rings as the major features. In both salts with 2‐picolinic acid, the specific R12(5) hydrogen‐bonding motif is observed. Structural studies have been enriched by the generation of fingerprint plots derived from Hirshfeld surfaces. 相似文献
13.
Birgit Waltenberger Judith M. Rollinger Ulrich J. Griesser Hermann Stuppner Thomas Gelbrich 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(10):o409-o412
The stereochemistry of the iridoid plumeridoid C, C15H18O7, was established by X‐ray single‐crystal structure analysis, giving (2′R,3R,4R,4aS,7aR)‐methyl 3‐hydroxy‐4′‐[(S)‐1‐hydroxyethyl]‐5′‐oxo‐3,4,4a,7a‐tetrahydro‐1H,5′H‐spiro[cyclopenta[c]pyran‐7,2′‐furan]‐4‐carboxylate. The absolute structure of the title compound was determined on the basis of the Flack x parameter and Bayesian statistics on Bijvoet differences. The hydrogen‐bond donor and acceptor functions of the two hydroxy groups are employed in the formation of O—H...O‐bonded helical chains. 相似文献
14.
Rosane de P. Castro Carolina da S. Matos Cludia A. do Nascimento Cecília M. A. Oliveira Lucília Kato Luciano M. Lio Jos R. Sabino 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(4):m94-m96
The absolute configuration of strictosidinic acid, (2S,3R,4S)‐3‐ethenyl‐2‐(β‐d ‐glucopyranosyloxy)‐4‐{[(1S)‐2,3,4,9‐tetrahydro‐1H‐pyrido[3,4‐b]indol‐1‐yl]methyl}‐3,4‐dihydro‐2H‐pyran‐5‐carboxylate, was determined from its sodium chloride trihydrate, poly[[diaqua((2S,3R,4S)‐3‐ethenyl‐2‐(β‐d ‐glucopyranosyloxy)‐4‐{[(1S)‐2,3,4,9‐tetrahydro‐1H‐pyrido[3,4‐b]indol‐2‐ium‐1‐yl]methyl}‐3,4‐dihydro‐2H‐pyran‐5‐carboxylate)sodium] chloride monohydrate], {[Na(C26H32N2O9)(H2O)2]Cl·H2O}n. The strictosidinic acid molecule participates in intermolecular hydrogen bonds of the O—H...O and O—H...Cl types. The solid‐state conformation was observed as a zwitterion, based on a charged pyridine N atom and a carboxylate group, the latter mediating the packing through coordination with the sodium cation. 相似文献
15.
Two stereoisomeric pentacyclic oxindole alkaloids from Uncaria tomentosa: uncarine C and uncarine E
Ilias Muhammad Ikhlas A. Khan Nikolaus H. Fischer Frank R. Fronczek 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):480-482
The chloroform solvate of uncarine C (pteropodine), (1′S,3R,4′aS,5′aS,10′aS)‐1,2,5′,5′a,7′,8′,10′,10′a‐octahydro‐1′‐methyl‐2‐oxospiro[3H‐indole‐3,6′(4′aH)‐[1H]pyrano[3,4‐f]indolizine]‐4′‐carboxylic acid methyl ester, C21H24N2O4·CHCl3, has an absolute configuration with the spiro C atom in the R configuration. Its epimer at the spiro C atom, uncarine E (isopteropodine), (1′S,3S,4′aS,5′aS,10′aS)‐1,2,5′,5′a,7′,8′,10′,10′a‐octahydro‐1′‐methyl‐2‐oxospiro[3H‐indole‐3,6′(4′aH)‐[1H]pyrano[3,4‐f]indolizine]‐4′‐carboxylic acid methyl ester, C21H24N2O4, has Z′ = 3, with no solvent. Both form intermolecular hydrogen bonds involving only the oxindole, with N?O distances in the range 2.759 (4)–2.894 (5) Å. 相似文献
16.
Balasubramanian Sridhar Krishnan Ravikumar Venkatasubramanian Hariharakrishnan 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1186-1191
Zolmitriptan hydrogen oxalate [(S)‐dimethyl(2‐{5‐[(2‐oxo‐1,3‐oxazolidin‐4‐yl)methyl]‐1H‐indol‐3‐yl}ethyl)azanium hydrogen oxalate], C16H22N3O2+·C2HO4−, (I), and zolmitriptan camphorsulfonate [(S)‐dimethyl(2‐{5‐[(2‐oxo‐1,3‐oxazolidin‐4‐yl)methyl]‐1H‐indol‐3‐yl}ethyl)azanium (S,R)‐{2‐hydroxy‐7,7‐dimethylbicyclo[2.2.1]heptan‐1‐yl}methanesulfonate], C16H22N3O2+·C10H15O4S−, (II), are the first reported salt complexes of the antimigraine drug zolmitriptan. Compound (I) crystallizes in the space group P21 with two molecules of protonated zolmitriptan and two oxalate monoanions in the asymmetric unit, while compound (II) crystallizes in the space group P212121 with one protonated zolmitriptan molecule and one camphorsulfonate anion in the asymmetric unit. The orientations of the ethylamine side chain and the oxazolidinone ring with respect to the indole ring of the zolmitriptan cation are different for (I) and (II). In (I), they are oriented in opposite directions and the molecule adopts a step‐like appearance, while in (II) the corresponding side chains are folded in the same direction, giving the molecule a cup‐like appearance. The zolmitriptan molecules of (I) form an R22(8) dimer, while in (II) they form a helical chain with a C(11) motif. The oxalate monoanions of (I) interact with the zolmitriptan cations and extend the dimer into a three‐dimensional hydrogen‐bonded network. In (II), the camphorsulfonate anion forms an R22(15) ring motif with the zolmitriptan cation. 相似文献
17.
The two dinuclear IrI complexes [Ir2(μ‐Cl)2 {(R)‐(S)‐PPF‐PPh2}2] ( 1 ; (R)‐(S)‐PPF‐PPh2=(S)‐1‐(diphenylphosphino)‐2‐[(R)‐1‐(diphenylphosphino)ethyl]ferrocene and [Ir2(μ‐Cl)2{(R)‐binap}2] ( 3 ; (R)‐binap=(R)‐[1,1′‐binaphthalene]‐2,2′‐diylbis[diphenylphosphine]) smoothly react with 4 equiv. of the lithium salt of aniline to afford the new bis(anilido)iridate(I) (=bis(benzenaminato)iridate(1‐)) complexes Li[Ir(NHPh)2{(R)‐(S)‐PPF‐PPh2}] ( 4 ) and Li[Ir(NHPh)2{(R)‐binap}] ( 5 ), respectively. The anionic complexes 4 and 5 react upon protonolysis to give the dinuclear aminato‐bridged derivatives [Ir2(μ‐NHPh)2{(R)‐(S)‐PPF‐PPh2}2] ( 6 ) and [Ir2(μ‐NHPh)2{(R)‐binap}2] ( 7 ), which were characterized by X‐ray crystallography. None of the new complexes 4 – 7 shows catalytic activity in the hydroamination of olefins. 相似文献
18.
Elena Buuel Carlos Cativiela María D. Díaz‐de‐Villegas Jos A. Glvez 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):587-591
The structures of two conformationally restricted 4,5‐dihydroxynorvaline analogues with a norbornane skeleton, namely methyl (1S,2S,3R,4R)‐2‐benzamido‐3‐(1,2‐dihydroxyethyl)bicyclo[2.2.1]heptane‐2‐carboxylate, C18H23NO5, and methyl (1R,2S,3R,4S)‐2‐benzamido‐3‐(1,2‐dihydroxyethyl)bicyclo[2.2.1]heptane‐2‐carboxylate, C18H23NO5, exhibit a conformation in the helical region of the ?,ψ map but their handedness is opposite. In both cases, the torsion angles (χ1,1) giving the relative orientation of the 1,2‐dihydroxyethyl group of the amino acid side chain and the benzamide group of the peptide chain indicate that these groups adopt a nearly eclipsed conformation. Both compounds show a complex hydrogen‐bonding pattern. 相似文献
19.
Barbara Wicher Krystian Pyta Piotr Przybylski Ewa Tykarska Maria Gdaniec 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(5):o209-o212
Rifampicin belongs to the family of naphthalenic ansamycin antibiotics. The first crystal structure of rifampicin in the form of the pentahydrate was reported in 1975 [Gadret, Goursolle, Leger & Colleter (1975). Acta Cryst. B 31 , 1454–1462] with the rifampicin molecule assumed to be neutral. Redetermination of this crystal structure now shows that one of the phenol –OH groups is deprotonated, with the proton transferred to a piperazine N atom, confirming earlier spectroscopic results that indicated a zwitterionic form for the molecule, namely (2S,12Z,14E,16S,17S,18R,19R,20R,21S,22R,23S,24E)‐21‐acetyloxy‐6,9,17,19‐tetrahydroxy‐23‐methoxy‐2,4,12,16,18,20,22‐heptamethyl‐8‐[(E)‐N‐(4‐methylpiperazin‐4‐ium‐1‐yl)formimidoyl]‐1,11‐dioxo‐1,2‐dihydro‐2,7‐(epoxypentadeca[1,11,13]trienimino)naphtho[2,1‐b]furan‐5‐olate pentahydrate, C43H58N4O12·5H2O. The molecular structure of this antibiotic is stabilized by a system of four intramolecular O—H...O and N—H...N hydrogen bonds. Four of the symmetry‐independent water molecules are arranged via hydrogen bonds into helical chains extending along [100], whereas the fifth water molecule forms only one hydrogen bond, to the amide group O atom. The rifampicin molecules interact via O—H...O hydrogen bonds, generating chains along [001]. Rifampicin pentahydrate is isostructural with recently reported rifampicin trihydrate methanol disolvate. 相似文献
20.
Sergio A. Guerrero Carlos M. Sanabría Alirio Palma Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(4):408-415
(2R*,4S*)‐Methyl 2,3,4,5‐tetrahydro‐1,4‐epoxy‐1H‐benz[b]azepine‐2‐carboxylate, C12H13NO3, (I), and its reduction product (2R*,4S*)‐methyl 4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benz[b]azepine‐2‐carboxylate, C12H15NO3, (II), both crystallize as single enantiomers in the space group P212121, while the hydrolysis product (2RS,4SR)‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benz[b]azepine‐2‐carboxylic acid, C11H13NO3, (III), and the lactone (2RS,5SR)‐8‐(trifluoromethoxy)‐5,6‐dihydro‐1H‐2,5‐methanobenz[e][1,4]oxazocin‐3(2H)‐one, C12H10F3NO3, (IV), both crystallize as racemic mixtures in the space group P21/c. The molecules of compound (IV) are linked into centrosymmetric R22(10) dimers by N—H...O hydrogen bonds, and those of compound (I) are linked into chains by C—H...π(arene) hydrogen bonds. A combination of O—H...O and O—H...N hydrogen bonds links the molecules of compound (III) into sheets containing equal numbers of R44(14) and R44(26) rings, and a combination of C—H...π(arene) hydrogen bonds and three‐centre O—H...(N,O) hydrogen bonds links the molecules of compound (II) into a three‐dimensional framework structure. Comparisons are made with some related compounds. 相似文献